Path of least resistance: the quest for room-temperature superconductors

We don’t talk enough about superconductors. These materials carry electricity without losing energy and could change the world – if only we could rediscover the kind of progress we used to make in this field.

We have known about superconductors since 1911, when the first one was discovered. In normal conductors – an aluminium wire at room temperature, for instance – electrons move through the material, jostled by all the other particles. Cool that aluminium down to -272° Celsius, though, and it becomes a superconductor. The electrons encounter no resistance, zipping along the wire as if they were the only particles in town.

That is significant: the copper cables used to transmit electricity from power stations to your home lose 10 per cent of energy through electrical resistance. If those cables were made of a superconductor, no energy would be lost. We would not need to generate so much power, reducing our dependence on fossil fuels.

Even better would be the ability to store energy. Renewable sources such as wind, wave and solar power generate energy at times and rates beyond our control. That power could be stored indefinitely in superconducting circuits. Because these don’t dissipate any of the energy, a superconducting power store is a battery whose charge lasts as long as you need it to.

There are also transport applications. Superconductors repel magnets and engineers have exploited this by putting superconductors on trains and electromagnets on the track. The repulsion levitates the train above the track, hugely reducing friction and clearing the way for ultra-fast transport.

So far, though, magnetic levitation trains have taken off in only a couple of places around the world. That is because superconductors are still not super enough. The main problem is that more energy is spent to cool materials until they become superconducting than is saved through reduced transmission loss, better energy storage capacity or greater transport efficiency.

This is a tale of dashed hopes. From 1911 to the 1980s, superconductors were available at temperatures below -240° Celsius only. We thought we had beaten this barrier in 1986 when we discovered a copper compound that was superconducting at -183° Celsius. Suddenly, things were looking up: we could turn materials superconducting by cooling them with liquid nitrogen, a relatively cheap and easy means of refrigeration.

However, it still wasn’t cheap and easy enough to make superconducting technology mainstream. So we cooked up more of these “high-temperature superconductors”. By 1993, we had got to about -140° Celsius. Things were looking very good indeed. And then, almost nothing. We are still less than halfway to room-temperature superconductors.

That’s because, despite decades of research, we’re still trying to figure out how they work. Progress is painfully slow. In October, French and US researchers finally confirmed a prediction, made in 1964, about one microscopic characteristic of what is going on inside superconductors.

This latest breakthrough might lead to superconductors that can withstand higher magnetic fields and thus give hospitals better MRI scanners – but it won’t push that critical transition point up towards room temperature. We can only hope that will be achieved by the researchers investigating other features of superconduction. No one thinks such a breakthrough is imminent. In an age when we have come to understand some of the deepest secrets of the universe, the secrets of the superconductor are keeping our feet firmly on the ground.

A quote-by-quote analysis of how little Jeremy Hunt understands technology

In today’s “Did we do something wrong? No, it was social media” news, Health Secretary Jeremy Hunt has argued that technology companies need to do more to prevent sexting and cyber-bullying.

Hunt, whose job it is to help reduce the teenage suicide rate, argued that the onus for reducing the teenage suicide rate should fall on social media companies such as Facebook and Twitter.

Giving evidence to the Commons Health Committee on suicide prevention, Hunt said: “I think social media companies need to step up to the plate and show us how they can be the solution to the issue of mental ill health amongst teenagers, and not the cause of the problem.”

Pause for screaming and/or tearing out of hair.

Don’t worry though; Hunt wasn’t simply trying to pass the buck, despite the committee suggesting he direct more resources to suicide prevention, as he offered extremely well-thought out technological solutions that are in no way inferior to providing better sex education for children. Here’s a quote-by-quote analysis of just how technologically savvy Hunt is.

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“I just ask myself the simple question as to why it is that you can’t prevent the texting of sexually explicit images by people under the age of 18…”

Here’s Hunt asking himself a question that he should be asking the actual experts, which is in no way a waste of anybody’s time at all.

“… If that’s a lock that parents choose to put on a mobile phone contract…”

A lock! But of course. But what should we lock, Jeremy? Should teenager’s phones come with a ban on all social media apps, and for good measure, a block on the use of the camera app itself? It’s hard to see how this would lead to the use of dubious applications that have significantly less security than giants such as Facebook and Snapchat. Well done.

“Because there is technology that can identify sexually explicit pictures and prevent it being transmitted.”

Erm, is there? Image recognition technology does exist, but it’s incredibly complex and expensive, and companies often rely on other information (such as URLs, tags, and hashes) to filter out and identify explicit images. In addition, social media sites like Facebook rely on their users to click the button that identifies an image as an abuse of their guidelines, and then have a human team that look through reported images. The technology is simply unable to identify individual and unique images that teenagers take of their own bodies, and the idea of a human team tackling the job is preposterous.

But suppose the technology did exist that could flawlessly scan a picture for fleshy bits and bobs? As a tool to prevent sexting, this still is extremely flawed. What if two teens were trying to message one another Titian’s Venus for art or history class? In September, Facebook itself was forced to U-turn after removing the historical “napalm girl” photo from the site.

As for the second part of Jezza’s suggestion, if you can’t identify it, you can’t block it. Facebook Messenger already blocks you from sending pornographic links, but this again relies on analysis of the URLs rather than the content within them. Other messaging services, such as Whatsapp, offer end-to-end encryption (EE2E), meaning – most likely to Hunt’s chagrin – the messages sent on them are not stored nor easily accessed by the government.

“I ask myself why we can’t identify cyberbullying when it happens on social media platforms by word pattern recognition, and then prevent it happening.”

There is simply no algorithm yet intelligent enough to identify bullying language. Why? Because we call our best mate “dickhead” and our worst enemy “pal”. Human language and meaning is infinitely complex, and scanning for certain words would almost definitely lead to false positives. As Labour MP Thangam Debbonaire famously learned this year, even humans can’t always identify whether language is offensive, so what chance does an algorithm stand?

(Side note: It is also amusing to imagine that Hunt could even begin to keep up with teenage slang in this scenario.)

Many also argue that because social media sites can remove copyrighted files efficiently, they should get better at removing abusive language. This is a flawed argument because it is easy to search for a specific file (copyright holders will often send social media giants hashed files which they can then search for on their databases) whereas (for the reasons outlined above) it is exceptionally difficult for algorithms to accurately identify the true meaning of language.

“I think there are a lot of things where social media companies could put options in their software that could reduce the risks associated with social media, and I do think that is something which they should actively pursue in a way that hasn’t happened to date.”

Leaving aside the fact that social media companies constantly come up with solutions for these problems, Hunt has left us with the burning question of whether any of this is even desirable at all.

Why should he prevent under-18s from sexting when the age of consent in the UK is 16? Where has this sudden moral panic about pornography come from? Are the government laying the ground for mass censorship? If two consenting teenagers want to send each other these aubergine emoji a couple of times a week, why should we stop them? Is it not up to parents, rather than the government, to survey and supervise their children’s online activities? Would education, with all of this in mind, not be the better option? Won't somebody please think of the children?

“There is a lot of evidence that the technology industry, if they put their mind to it, can do really smart things.”

Alas, if only we could say the same for you Mr Hunt.

Amelia Tait is a technology and digital culture writer at the New Statesman.